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Questions in chemistry

[Done] A copper rod that has a mass of 200.0 g has an initial temperature of [tex]$20.0^{\circ} C$[/tex] and is heated to [tex]$40.0^{\circ} C$[/tex]. If [tex]$1,540 J$[/tex] of heat are needed to heat the rod, what is the specific heat of copper? Use [tex]$q=m C_p \Delta T$[/tex]. A. [tex]$0.0130 J /( g { }^{\circ} C )$[/tex] B. [tex]$0.0649 J /( g { }^{\circ} C )$[/tex] C. [tex]$0.193 J /( g { }^{\circ} C )$[/tex] D. [tex]$0.385 J /( g { }^{\circ} C )$[/tex]

[Done] What is the chemical formula of the compound copper(II) phosphate? Use the list of polyatomic ions and the periodic table to help you answer. A. $Cu _3\left( PO _4\right)$ B. $Cu \left( PO _3\right)_2$ C. $Cu _2\left( PO _4\right)_2$ D. $Cu _3\left( PO _4\right)_2$

[Done] Radhika has four beakers, and each beaker contains 100 ml of acidic solution. The amount of acid in each beaker is given below. Beaker 1 - 50 ml of acid Beaker 2 - 25 ml of acid Beaker 3 - 80 ml of acid Beaker 4 - 75 ml of acid Arrange these solutions in the order of their concentration, starting from the most diluted.

[Done] What are the substances you end up with in a chemical reaction called? A. The reactants B. The products C. The resultants D. The solution

[Done] Ammonia $\left( NH _3(g), \Delta H_{ f }=-46.19 kJ / mol \right)$ reacts with hydrogen chloride $\left( HCl ( g ), \Delta H_{ f }=-92.30 kJ / mol \right)$ to form ammonium chloride ( $NH _4 Cl ( s ), \Delta H_{ f }=-314.4 kJ / mol$ ) according to this equation: $NH_3(g)+HCl(g) \rightarrow NH_4 Cl(s)$ What is $\Delta H_{ rxn }$ for this reaction?

[Done] Classify the following substances into elements and compounds. Elements: Silver Oxygen Iron Carbon Compounds: Salt Hydrogen chloride Water Sodium bicarbonate Hydrogen iodide Gold

[Done] Consider the following reversible reaction. [tex]CO(g)+2 H_2(g) \longleftrightarrow CH_3 OH(g)[/tex] What is the equilibrium constant expression for the given system? A. [tex]Keq =\frac{[ CO ][ H 2]^2}{\left[ CH _3 OH \right]}[/tex] B. [tex]Keq =\frac{\left[ CH _3 OH \right]}{[ CO ][ H 2]^2}[/tex] C. [tex]Keq -\frac{[ CO ][ H 2]}{\left[ CH _3 OH \right]}[/tex] D. [tex]Keq =\frac{\left[ CH _3 OH \right]}{[ CO ][ H 2]}[/tex]

[Done] How many protons and neutrons are in an atom of Am-241? Number of protons = Number of neutrons =

[Done] What would dissolve the best in oil? A. Salt B. Grease C. Water D. Sugar

[Done] Hydrogen reacts with chlorine to form hydrogen chloride \(\left( HCl ( g ), \Delta H_{ f }=-92.3 kJ / mol \right)\) according to the reaction below \(H_2(g)+Cl_2(g) \rightarrow 2 HCl(g)\) Which statement is correct? Use \(\Delta H_{\text {pon }}=\sum\left(\Delta H_{\text {f.products }}\right)-\sum\left(\Delta H_{\text {f.reactants }}\right)\). A. The enthalpy of the reaction is -184.6 kJ, and the reaction is exothermic. B. The enthalpy of the reaction is -184.6 kJ, and the reaction is endothermic. C. The enthalpy of the reaction is 184.6 kJ, and the reaction is endothermic. D. The enthalpy of the reaction is 184.6 kJ, and the reaction is exothermic.